Scenery handling apparatus



June 28, 1960 G. c. IZENOUR & 3

SCENERY HANDLING APPARATUS Filed Nov. 5, 1957 8 Sheets-Sheet 1 q II INVENTOR 0 415026: (Ilir/7002 June 28, 1960 Filed Nov. 5, 1957- G. C. IZENOUR SCENERY HANDLING APPARATUS 8 Sheets-Sheet 2 INVENTOR.

` June 1960 e. c. IZENOUR 2,942,879

SCENERY HANDLING APPARATU Filed Nov. 5, 1957 8 Sheets-Sheet 3 r I l I I] INVENTOR.

June 28, 1960 G. c. IZENOUR v & 3

SCENERY HANDLING APPARATUS Filed Nov. 5, 1957 8 Sheets-Sheet 4 1 N V EN TOR. 624. 65 (I 12 191 0146 June 28, 1960 G. c. IZENOUR & 3

SCENERY HANDLING APPARATUS Filed Nov. 5, 1957 8 Sheets-Sheet 5 w sa l N V E N TO R & aca; (5125/7062 ATTORNEY June 5 G. c. IZENOUR 2,942,879

SCENERY HANDLING APPARATUS Filed Nov. 5, 1957 8 Sheets-Sheet 6 70 F/CESC ATTORNEY June 28, 1960 G. c. IZENOUR SCENERY HANDLING PPARATUS 8 Sheets-Sheet 8 Filed Nov. 5, 1957 F/GJO T A H United States Pater't 2342379 SCENERY HANDLING APPARATUS George C. Izenour, Alsto Ave., New Haven, Conn. i Filed Nov. 5, 1957, Ser. No. 694 583 31 Claims.' (c. ;72:42

The present invention relates to apparatus for handling scenery, as in a theatre, and has as its broad purpose the provision of a new system for Operating scenery in order to change 'sets at difiere'nt times, as during a performance.

In typical theatre Construction, the stage is provided with scene'ry that is suspended from lines or cables extending from above, and the sceney is changed by lifting one or 'more scenery units and lowering others. The region where the raised sets are stored, to be lowered Selectively as demanded, is called the dijes or the flyloft. ,The wings of the theatre are to the left and right of the stage, and the entire area 'of the stage, above the fiies, is covered by a grid or gridiron. The high i'ro'n, which is the supporting structure for the roof over the stage, is spaced above the gridiron suficiently higher to 'provide the'necessary working space.

For literally centu'ri'es there has been a standardized type of construction that is used almost 'universally at the present time for raising and lower-ing the scenery. If a single flat is considered as a typical unit of scehery, there will be multiple spaced lines (four lines is usually standard) attached to horizontal 'pipes 'or battens supporting this flat. These lines exte'nd Upward from the fiat to individual pulleys supported by the gridiron, and these lines all extend horizontally to one side of the stage. Each line has a separate pulley, normally where ,it reaches the gridiron, but all of the lines will extend `to a common pulley at the lateral edge of the gridiron. ,Each common pulley and all the individual pulleys having lines to a batten are in a straight line extending :directly crosswise of the stage. Each set of lines extends over its common pulley to a common counter'weight. 'The pulleys for the different'sets are in a row at one side -of the stage, and the counterweights hang down below them, requiring a vertical Operating space that *equals .the distance that the scenery must be lifted.

Each common pulley is limited almost invariably to four lines so that large and heavy sets may requir'e special treatment. The alignment of each group of individual ,pulleys transversely across the stage involves complica- :tions when sets are to be handled that have substantial t'depth. v g I A gallery is usually provided aloft 'near the common :pulleys at the edge of the gridiron, where a stage hand =can load weights to balance each new unit of scenery. The space below the'com'rnon pulleys where *lines extend .to the counterweights'is waste. Operating lines also hang down to stage level for manual operation for lowering :and raising the scenery. This represents an allocation aot space between the stage and one of the wings that may anism. A still further object is to clear the space -at the lateral limits of the stage formerly allocated to scener'y Operating apparatus, to make it' freely available for other use.

An addtional object resides in the provision of 'nbvel apparatus that eliminates the manual operation of pulley- Operating lines, by substituting remote-controlled eletri 'cally powered apparatus. Through this feature of ;the invention, the change in scenery can be accomplishd at greater speed (a most important consideration in 'se ne dramatic presentations) and it may be accomplished -t an architecturally convenient location. The simple opetation of electrical controls is effective to shift any desir'el sets as fast as desired, limited only by the motor power and the strength of the lines 'and of the sets.

In another aspect, a basic object of the present invention is to *provide novel highly flexible apparatus for handling scenery. The novel stage organization made possible by this aspect of the invention is not restricted and confined to the previous requirement of each group of -lines eXtending to a common pulley, nor 'to the use of any particularnumber of lines for a unit of scenery nor to the previous 'requirement that the individual pulleys for lines 'An important feature of the present invention resid'e's in the use of electric motor driven winches for individual "lines to a set and in the Coordination of such meters.

Through this basic departure from standard practice, each motor and each winch can be located wherever may be convenient. cat'ed at any desired position. This flexibilty at once opens up the possibility of broad architectural change from conve'ntional back-stage theatre designs. The sideof the stage previously reserved for counter'weights, Operating lines, and the ass'ociated common pulleys can be made open and clear, free for new uses. The counterw'eight loading gallery is also eliminated, and the proc'edure of -balanci'ng the weight 'of the set with counterweights is also eliminated. Electrically coordinated motor-driven winches are used that are individual to each line; and 'there is no longer any need for lines xtending infiexibly from respective pulleys in the g'ri'diro'n toward the common pulleys, nor is there a'ny arbitrarily limited number of lines that may be operated in unison. The invention makes it possible for any line to e'xten'd in any convenient direction to any available which. 'A related feature of the invention resides in the provision of supports for individual sheaves virtually anywhere that may be de'sired, without the restriction heretofo're of "r quirng individual pulleys of a group of linesto be ni'cely in line across the stage.

'Further features of the invention reside in 'the provision of rows of firmly supported electric-motor driven wincles at any convenient locations above 'the fli'es, as for example spaced'along the'rear of the stage or-'t'tlfe side of the stage or across the front of the stage, -or 't all suchplaces. 'No longer it is necessary for allof the lines from a ;given piece of 'scener'y to eX'tend all the w'y across the stage to a common pulley. With the present system, each line can extend to the nearest convenient accessible motor-driven winch. Each line need be -no longer than necessary to reach the closest available winch. With the new system a line from a scenery element near the center of the stagecan extend to a winch at the rear, and lines from the same scenery element that a'enear the sides of the stage can extend "to winehes at the sides of the stage, all of the winches for handling a 'stage set being coorclinated electrically.

With the novel system it will be 'apparent that' the lines extending Upward from the scene'ry to pulleys or sheaves will usually extencl from those sheaves in various direc- The control apparatus may also -b'e lo- -handles-one line.

, controls provided. These include provision for ;automatically limiting the extent of raising and' lowering ;of the various sets, as Well as for reducing speed as teach limit' is approached, while maintaining proper co- :ordination of the winches; in the selection of each group -of winches; and the provision of means for concurrent operation of two groups of winches for simultaneously ;raisng one stage set and lowen'ng another.

The foregoing objects and features of the -inventon are accomplished in the illustrative embodiment described in'detail below. In'this embodiment, briefly, a series of winches are provided for the 'individual lines extending to sets or units of scenery. The lines for handling each set extend to physically independent winches which are electrically coordinated. Each winch Each winch isdriven by an individual electric motor. The control apparatus enables any combination of winches that may be identified with a pari ,ticular set to be connected for common control and energizaton Two controlled power sources are pro vided and selective controls enable each source to be switched to each successive group of motors while the .other source is applied to any other selected group of -motors for concurrent operation but 'separately controlled ,as to speed and direction.

A feature promoting sustaned Coordination resides in the use of synchronous type motors for the winches,

and controlled-frequency sources of alternating current -for speed ,control of all winches Operating a unit of scenery. Electric motors of other types capable of sharing the load of a set can alternatively be used in applying 'certain broader aspects of the inventon.

As a detail of specific importance, the winches are ideally of a form where the length of line taken in or paid out per motor rotation is constant, and where the 'point at which the line reaches its winch is constant, ,so jthat, with equal motor rotations and uniform han-` dling of the several lines of a set, initially established sharing of the load is maintained.

With the foregoing background, the features of the :illustrative embodiment described below will be readily appreciatd, and from this description additonal objects -and features ,of novelty will become apparent. The'illustrative embodiment of the invention is shown in the accompanyi'ng drawings forming part of this disclosure.

.Inthe drawings:

' Fig. 1 is the cross section of a portion of a theatre showing the stage thereof, to which ;the invention lis applied;

. Fg. 2 is a vertical fragmentary cross-section along the line '2 2 in Fg. 1, drawn to a larger scale;

Fig. 3 is a planview of the structure in Fig. 2;

Fig. 4 is the side elevaton of a' typical novel winch *and related structure shown in Figs. 1 to 3, Fig. 4 being drawn to larger scale; V

support in Fig. 4, the section being taken l g the lille ssinFi 4; j

Fig 5 is an elevaton of the winch in Fig. 4 viewed V from the right thereo-f;

' to the rear of the stage.

Figs. 9a, 917 and 9c are the wiring diagram for control and Coordination of a system 'of winches illustrated in the other drawings; and

Fig. 10 is an elevaton of conventional scenery handling apparatus view as per Fig. 2.

Referring first to Fig. 10 there appear certain typical elements of conventional scenery-handling apparatus, supplementing the brief description above. cratus is widely used and has been in-use for several centuries. (The numerals used here are primed numerals corersponding to those used in the description of apparatus in Figs. 1 to 9 which follows.) 'In Fig. 1 0 the stage 10' has a flat 24' carried by lines 26' which extend over pul1eys 29' carried by the grid 32'. All of the lines 26' extending from a single scenery unit 24' .extend to a common pulley 20' and from this'pulley to a common counterweight 19 which counterbalances the entire load of the scenery unit 24'. Pulley 20' is suitablysupported from wall 22', this wallextending down to the stage, or to a point close to stage level Wall 22' additionally carries a gallery 21 close to the grid level, where a supply 'of counterweights is stored and where the sets, when being installed, are counterbalanced. Weights are added to the group of lines 26' until the scenery unit is accurately counterbalanced. Thereafter, 'the weights are lowered andfthe set is elevated, or the can be supported by this arrangement 'of lines. Each common pulley 29' can accommodate four lines, so that no more than this number of lines ?can be used for an individual set, regardless of its shape, size or weight. Pulleys 29' are supported on rails extendng front-torear above the stage at a wide separation, which is a further limitation on the usefulness of the system. It is feasible to adjust the position of each pulley 29' per* pendicular to the View, toward and away from the front of the stage; but all of the pulleys together with pulley 20' are required 'to be adjusted so as to remain inline.

In view of the requirement that all of the lines 26' attached to a given flat 24' shall move together, they must all be operated by the same pulley 20' and therefore, if a single stage set extends all the way across the stage, the line to the most distant part of the scenery must also extend all the way across the stage, from the most remote vertical line to the pulley 20'. i

The common pulleys, counterweights' and Operating lines, being located only at the side of the stage, preempt the'space there which might be used for other purposes. Thewalls 22' also support the weight-loading gallery 21.

The grid 32' must be strengthened as by tie rods 33 extending to the high iron 18' to support the pulleys 29' for handlng stage scenery can be extended for better appreciation of what is involved by reference to standard works on this subject as for example, that by Cole, Burris- Meyer entitled. scenery for the Theatre. i

Referring now to Figs. 1 to 3 inclusive, the stage 10 of a theatre is illustrated, having a front wall 12 in which there is formed a prosceniurn 14 through which performances are witnessed, and a rear wall 16. The roof of the stage is supported by so-called ***high-iron 18 being usually a number of parallel I beams extending from the front A series of winches 20 are shown extending along the front and back walls? of the stage, and also against side walls 22 (Fig. 2) depending a short distance from the high iron 18. One such side wall 22 depends from the highiron at each side of the stage, leaving thespace below these walls 22 at both sides of the st ge completely free and clear, This is the space Such appa- It therefore becomes necessary to provide scenery of such design that l'ater).to indicate the rotational position of shaft 58 and,

may ;be readilyunderstood. When :tension is developed inline 26 extending from sheave 29 to guide pulley 48 oflthe winch, that 'guide pulley is lined up with the sheave. If the selected Winch is not in line with T-sh'aped sheavehangr 30, treme 44 of the winch swings about its pivot so as-tobring pulley 48 into 'alignment with its sheave 29. (Before line 26 is tensioned, pressure roll l shown in Fig. 7 prevents loosening of the line). Opration of motor 52 rotates shaft 58 through the Worm dr'ive, 54 -'56, line 26 Winds or unwinds, depending upon `the direction of motor drive. Drum 60 is gradually raised or lowered by the threaded lower portion of shaft 58 operating in threaded hearing 50, in order that thegrooves of drum 60 will be in proper relation to reeive or pay ofi the line 26. The provision of the worm drive is important, in-that this drive prevents tension in line from rotating shaft 58, that is, the worm drive is self-looking land is not capable of mechanically reversed operation. Rotation of the worm wheel 56 cannot take place in a way to 'drive the Worm 54. This worm drive 54--56 is in one-way drive in the sense that mechanically the member 54 is always the drive member and member56 is the driven member. In this way, the weight of [the set -carried by line 26 is inefiective to drive ;the 'worm gearing in reverse so that, when motor 52 is idle, the position of the set is fixed. The term one way r mechanical drive is used in referring tothe driving memberin relationl to the driven member, and notto the rotational sense. Motor 52 is of a type to be electrically eversi ble for either rotational direction, for winding up or paying of a desired length of line 26.

In the course of reeling in or paying out some of line 26,-because drum 60 moves to maintain a common winding point atguide-wheel 48, the distance from the winding point of the winch to the sheave 29 is constant.

Itwill also be recalled that the vertical portions of lines 26 are parallel and are moved in equal increments by the coordinated winches( Hence all of the winches maintnin their respective shares of the set load regardless of vertical position of the set and regardless of the random angles (note Fig. 3) that may result in the choices of winches for each set.

Drum 60 may, for example, be of four-inch diameter and 12 inches long, with close-spaced grooves for receiving /s diameter steel cable. Such a drum can store 90 feet of cable.

Synchronous electric motors 52 for the various winches are operated and coordinated by remote control, from a console at a'convenient location, preferably at a point firom which full view of the stage may be had. The wiring diagram of that portion of the illustrative system that isinstalled aloft with the winches is shown in Fig. 9a; the ,wiring diagram of the console is in Fig. 9b; and the wiring diagram of the power supply and its associated Controls appears in Fig. 9c.

The system includes two separate sources of power, `so that it is entirely feasible to raise one set and simultaneouslylower another set, each at its own rate and each s topping independently, as required. This feature is highly desirably in dramatic situations where quick change ;of sets is all-important.

In Fig. 9nt, nine winches are shown, with a suitable-number of these including transmitter synchros 62 and the others, labeled, 20a, a lacking these synchros. Eachmotor 52 is connected by a first relay 80 to power lines 82 that are connected to a controllable alternator 84. (Eig 9c) suitably located in a' sub-stage installation, for example. Motors 52 can, alternatively, be connected by respective relays 86 to the, power lines 88 from anptherrremotely ;located alternator 90. A common mehanical'drive motor 92 operates alternators 84 and-90 through electrodynamically *controlled drive' couplings,

94 and 96, respectively.-

form of drive, the dynamic couplings 94 and 96, may be Compared to a clutch which may be either eifectvely disengagedso as not. to drive it s generator at all, or it may notslip at all so as to drive-its generator at-the full speed ot motor 92 or the dynann'c couplingnay "slip controllably, to provide any desired rate' between dead stop -and full motor speech; The 'speed ofthe alternator determines the frequency ot its output and this determines the speed of eachf synchronous motor 52 connected to it.. Dynamic couplings 94 and 96 have theircontrol devices 98 and 100.' These dynamic couplings and their controls are well knownendtheir details, forming no part ofv this invention; are not; herein described. In one form, the dynamic coupling may-be an eddy current clu tch whose control gradually increases the eddy current field to increase the tightness of coupling; Thyratrons -with adjustable grid-bias circiit are useful to control the eddy current.- r

a control wire 102, which wires may be joinedatogether.

Unit 98 has a maximum speed connection 104 anda minimum speed 'connection 106, whereas dynamic coupling control unit 100 has its maximum control wire 108 and its minimum speed control 110. A potentiometer'112 (Fig. 9b) is provided which enables manual selection of any desired speed between minimum and maximim of generator 84 and Similarly a potentiometerll4 is provided for enabling ,adjustment of the speed of operation of generator 90 to any value between' its minimuni and maximum speeds as controlled by wires 108 and 110. V

' Each alternator 84 and 90 can be connected to its respective power lines 82 and 88 for Operating the winch motors 52 in either -rotational direction. This depends upon the phase rotation of themotor, in relation to the connections of the generator to the line. Either phase relationship can be established by selecting the appropriate motor Starter 116 or 118. Motors 52 are all phased for like rotation when connected to -lines 82. *Starter 116 *may be phased to connect the alternator 84 to lines 82 for raising the sets, and Starter 118 is then oppositely phased-to connect alternator 84 to lines 82 'forlowerig the sets. Each motor starterfunctions for all the motors connected to the three-phase lines 82 'or 88. Similarly three-phase generator 90 can be connected to its power line 88 by starters 120 and 122 respectively, for either raising or lowering the sets operated by motors connected tothat power line. Starter selecting switch 124 is provided in the console (Fig. 9b), having one section 124a connected by wire 11611 to the "Up" starter1116 andanother section 124b connected by wire 118a to the Down' Starter 118 at the output of alternator 84. Similarly the Starter selecting switch 126 is provided in the console, having one section 126a connected by wire 1204 to the Up" Starter 120 and another section 126b connected by wire 122a to the "Down" Starter 122 at the output of alternator 90. These starters connect power to all of the motors which, at any given time, are connected to the respective power lines 82 and 88 bythe various relays and 86 (Fig. 9a). V

' switches 124 and 126 are three-position switches so as to have a neutral position, an Up position and a "Down position. Normally these switches are in their neutral position. Switch 124 is, however, shown in position to operate the motors and winches of the generator 84 and its power line =82 in the "Up" direction whereas switch 126 is shown in position to operate the motors 52 connected to lines 88 of alternator in the Down direction. Normally these switches 124 and 126 are moved away from their neutral position' for operating the respective starters only after selection of the yarious motor-winches had been elected as will appear below.

In the control console, there is a receiver synchro 128 that is connected by wires 129 ,to a respective transmitte:

synchro 62; Single phase power is ontinuously fed to thetransmitter synchros 62, but switches 130 can discontinue the supply of single phase power to the receiver synchros, when they are not required to function. Each synchro 'causes a travelling dog or switch operator 134 to move along the threadedshaft 132 in synchr'o'nism with the travel of the end of a line operated by the ,win'cl' that' alsodrives the transmitter synchro 128. When 'switch o'pertor134is near its lower limit, the scenery element carried by the related line is also near its lower limit and conversely when switch operator 134 is near its top limit th en the scenery carried by the winch that operates the' rjel atedtra'nsmitter synchro 62 is near its upper limit, in theflyloft 'above the stage. This operation o'ccurs, nattu'ally; when switch 130 is closed 'so that the transmitter and the recever synchro operate in synchronism. When switch 130 is open and synchro 128 is idle, diagrammatic'allyilln'strat'ed handle 135 can be used to' manually operafe shaft 132 and Shift the dog 134 to any desi'red position, i'n setting up new scenery. Associated with' threaded shaft 132 and travelling dog' 1 34 are switch bas'es 136 and 138, which ate suitably adjustable in relation to sh'aft 132 and in relati'o'n to each other. The Up' stop limit switch 140 is carried by the switch base 136 and the Down' limit switch 142 is carried by the base 138. As willmore' clearly' appear below, switches 140 and 142' ar'e in series respectively, with Contacts 124a and 124b of direction control switch '1 24 aiidwith one of the starters 116 'and 1-18 when' alterntor 8:4 is selected This series circuit is, however, ncomplete selector switches described below have been operated. Baes 136 and 138 also carry anticipatory ratecont'rol switches 144 and 146 respectively, having contacts 144a which are normally open and 144b which are normally closed as well as Contacts 146a that are normallyop'en and 146b which are normally closed.

In the operation of shaft 132, the travelling dog 134, moving fronrthe center, first engages rate control switch l 44` or 146 (depending upon the travel directio'nl and fe gardle ss of which rate-control switch is first operated the control unit 98 is effective to cut down the speed and output frequency of alternator drive ettectedby dynamic coupling 94 or 96, as the case may be. As a result, winches energized by the alternator may change in' speed from 2 feet per second to two inches per second Bases 136 and 138 are adjusted so that this occurs during the final 3 feet of travel of each set. Scale 147 associated with each screw 132 provides indication of the position of the related set. As will be understood more fully below, a'separate assembly 132 147 is provided for each set that is to be handled separately. V i

Travel of dog 134 beyond either rate control switch 144 or 146 is effective to open limit switch 140 or 142 (depending upon whether the operated winches are operated 'for raising or lowering 'a set) and opening of either of these switches (with the corresponding Contacts 124a or 124b closed) is efiective to stop the drive for the generator 84 or 90 by the motor 92, through the dynamic coupling 94 or 96;

In the foregoing description it has been presumed that a group of motors 52 are connected to the bus 82 supplied by generator 84 through one of the starters 116'or 118 depending upon the setting of direction control switch 124. Selective controls are provided which enable the switches 140, 142, 144 and 146 to be connected in control relation to the control unit 98 of generator 84 (there'- by controlling the power delivered to bus 82) or, alternatvely, for enabling the switches 140, 142, 144 and 146 to be connected to the control unit 100 of generator 90, thereby toontrol the power delivered to the three-wire busSS. Theoretically any set of these rate* and limit switches could be connected simultaneously to either generator control unit 98 or 100. However, this is undesirable. If both were to be so connected, then the efl'cfs of these switches would be' confused. The receiver 10 i synchi'o 128 relatedto one group of winches 20, and' 'the' cofre'spndin'g switches 140, 142, 146 and 148 cn Be expected to be proper for only one stage set; and `cons= que'ntly no two groups of winches should be operated from the sar ne alternator concurrently with the syncne operatedc'ontrol switches shown. Where two groups of winches are to 'be operated, they are connected to the two diiferent power Supplies provided. In that 'connection each one Controls its own power supply, as' described above. The' selective control means for connecting the switches 140, 142, 144 and 146 toone or the other of the control units '98 and :100 take the form of push buttons` in the illus'trative example, although naturally suitable' rotary switches 'with the proper nmrber of decks, 'jr push buttons and muti-contact relays having 'the interlo'cks like those provided for" the illnstrated push butto'n' example', m'ay be substit utedfif de'sired.

A pair of push buttons 150 and 152 are shown, having a 'centrally pivo'ted interlock 154 that prevents 'both of the push 'buttons 150 and 152 from being 'simultane ousl'y depressed. These push buttons have a neutral post tion, and each one 'of them also a depressed position Push button 150 simultane'ously closes five fs'ets of contacts 15021, 50b, 1500, 150d and 150e. Simflarly five: setsof'contacts are'operated by push button 152, nanrely contactsl sz, 15217', 1526, 152d and 152e. The *push buttons zso 'and 252 at the right in Fig. 9 operate con esponding switch Contacts, and any added number 'of push: buttons and switches 350 and 352, etc., may 'be provided, cofresp'ondirg ttlie number of stage sets that are tobe: handled separately. By means of a diagramma'tia'lly' illustratd interlock 151, only one push button 150- 259-350 be depressed 'at any one time, and 'a like: interlock 153 presente rno're than one push button 252-352 froni 'big depressed at any one time. avoids the difiiculty described above, of having 'plurat sets of winches on o`iie alternator at one time, with conicting ra'te 'and 'stop' rate' Controls.

The 'p'perset ofcontac'ts 150a and 15211 are provided for contrlling the relays 80 and 86 (Fig. '9a) for connecting" motor 52 to the selected lines 82 or 88 of g'en erator '84 or 90. Wires 155 and 157 from these two relays '80 and '86 eXtend to a two-prong plug 156 that fits a receptcle 158 forming 'part of a patch panel i the control console. When plug 156 is inserted receptacle "158, assuming that all other Controls are' appropriately effective, motor 52 will operate with the power delivered by the selected generator, under control of the rate and limit switches controlledby the receive? servo 128. Any number of additior'al motors not having transriiitter synchros (or not using them) can 'be V coordinated with inotor 52 simply 'by 'plugging their plug's 156 intodditi'onal parallel-cor'irected receptacle 158 as illustratecl, 'which will accordingly energize one of the control relays 86 or 83 of those additional motors 52 and thereby connect the additional motors to the same generator for 'coordinated operation. Thus, closing up Contacts 15051 will cause r'elay 86 to connect its related motor 52 to wires '82 of generator 84 whereas closing of contacts 152`c 'will cause relay to connect .that motor 52 to bus'88 of generator 90. All other winch motors plugged into the same groupof parallel-connected receptacles 153 will also be connnected to the 'same generator and will be 'subject to the sam'e'rate varia tion and interrliption of drive, in accordance with the controlled power delivered by that generator.

The' safetylever 154 makes it impossible for both Contacts a a`id 152a to be 'simultaneously closed. This' would be damagiig (in the absence of safety *devices in series with'the relay Contacts of relays 80 and 86) for in that event both generators'would 'be connected 'simultaneously to 'o'ne 'of the motors and accordingly .both .generators would be connected to each other. 'P'sh button control 'lvr '1'54 prevents this. ,i

Fush' button 150 when 'depressed 'connects *p"`*lnt switch 140 via wire 160 through contacts-150b and wire 162 to a bus' 164. This is connected to Up contacts 124fof the direction switch operates the Up motor Starter 116 of alternator 84 provided that the Up contacts 124a are closed (as shown). As previously mentioned, the direction control switch' 124 is moved from itsno'rmal neutral position only ?after depression of a selected pushbutton 150 (etc.). This .closes contacts 150 and causesthe relays 80 (or 86) to connect their respective motors 52 to the supply lines 82 (or 88), before those' lines are energized and thus spares 'relays 80 and 86 from the more severe duty of a motor Starter. Closing of Up contacts'124a operates the motor Starter 116"and energizes lines 82 of generator 84.

operation or push button 150 similarly closes contacts 1502, to 'complete a circuit from Down limit switch 142, via wire 166 and wire 168 to bus 170 and to 'fDown"`contacts 124b of directional switch 124. In similar fashion to the Up control circuit just described, thiscauses closing of the Down motor Starter 118 and energizes lines '82 to operateall winch motors thrown onto lines' 82 by their relays 80 under control of patch panel156- 158 and contacts 150a. i i

If either "Up" limit contacts 140 or Dowf limitcontacts 142 should be open when the group of winches are tobe driven down or up, respectively, that fact would not disturb the manner of operation described. The

'limit contacts 140, 142 are in series only with the related contacts of the directional switch 124.

operation of pushrbutton 152 closes' contacts 152b and 152e, and connects switches 140 and 142, respectivel y,`to direction control contacts 126a and 126b that art-,effective to throw alternator 90 on its lines 88. The operational details and efiects are'no difierent from that described in connection with contacts 150b and 150e, and need notbe reviewed further. 1

j" Pushbutto'n 150 is also effective to close contacts 1500 thereby to' connect the open side of contacts 144a and 146a via wires 172 and 174 to minimum speed connection 106 of a control 98 for alternator 84. At the same-time, push button 150 closes contacts 150d to complete a circuit 'extending from control wire 102 of unit 98 (Fig. 9c) through contacts 146b (Fig. 9b) and contacts 144b extending via wire 176 and contacts 150d to wire 178 to bus 180 and the slide contacts of potentior'neter 112. If either of contacts 144b or 146b is open,

as when the related winches are at one extreme position, I

this circuit to potentiometer 112 is broken. Moreover other contacts 144a or 146a would then be closed, connecting "CTL wire 102 via wire 172, contacts 150c and lead 174 to the minimumi speed wire 106 of the dynarnic coupling'control 98. This means that starting with dog 134 at either extreme, the scenery handling operation willproceed slowly until the respective switch 144 or 146 is thrown to the position shown in the drawing, after which high'speed operation'will commence; and it will continue until automatically reduced by dog 134 Operating the other rate control switch 146 or 144. If push button 152 were operated in place of' push button 150, the same series of connections Would be cstablished, linking contacts 140, 14 2, 144 and 146 with the control circuits of alternator 90, and repetition of detailed description is evidently unnecessary. It is evident, accordingly, that any push button 150- -250-350 is eective to conn'ect'its relatedswitches 140, 142, 144

and 146 in control relation to alternator 84 while push buttons 152--252-352 are efiective to connect its related contacts like, 140, 142, 144, 146 to the control circuits of alternator 90. Each push button throws its related group 'of winch motors to the linesfrom such alternator, byyirtue of push button contacts 150a or 152a (etc.), its related patch panel 156-158, and relay 80 or 86 (but riotboth, because of the safety interlock 154 that bars closure of both contacts 150a and 15211).

.The general operation of .the control system may now be -reviewed operation *of* the -console push buttons 150,'152, etc. control selection of winch motors in groups asdetermined by the patch panels 156-158, and the push buttons `also determine 'which alternator will supply power to eachselectd "group of motors. Thereafter opei'ation of the direction control switches 124 and 126 will connect the alternators to the respective three-wire lines via selected motor starters 116, 118, and 122 to operate thejgroups of motors in the desired directions. In the Console', even though one stop switch 140 or 142 is open, the selected groups of motors will operate. if the power phasing' is right for Operating the winch (and the receiver synchro) toward the opposite At first 'the rate of operation is low, but after the travelling dog 134 leaves the limit switch 140 or 142 and reverses the adjacent switch 144 or 146, the rate of operation changes to .high. ,This rate continues until dog 134 reaches the opposite rate control switch, Whereupon the speed drops; and the drive stops when the opposite stop switch is operated by dog 134. The rate may be low, at two inches per second, when the sets come close to the level of the stage, and a high speed, of two feet per sec ond' 'for example, may be in etfect'outside the top and bottom limits of travel of the set. Scale 147 opposite dog 134, displayed on the Console, indicates at the control point where the set is during its travel. i Units 94 and 96 are adyantageously of such design as to cushion any abrupt rate change.

In setting up a new series of sets, lines 26 are connected to them from individual winches. The winch motors are operated individually by plugging the related plug 156 into a patch panel, depressing a related push button, and throwinga direction control switch. This manually controlled operation of a single motor at a time is carried on for each motor having *a line connected to a scenery unit until all the supporting lines 26 a re taut, with the set at stage level. It makes no difference at this stage which motors 52 have synchros. This is 'because the switch of the synchro related to the push button circuit used at this time is open and dog 134 can be set at a mean point by manipul'ating handle 135, thereby to enable full-speed operation of the motors or operation of the motors'at any lower desired speed under control of manually adjusted potentiometers 112 and 114. During this initial operation switch 124 or 126 can be reversed to reverse operation of a supporting line 26, and operation can be quickly interrupted by moving switch 124 or'126 to -its neutral position so as to deenergize both starters 116 and 118 or 120 and 122, depending on which switch 124 or 126 is used.

When a group of individual lines have been adjusted so that they all share the load of the set, all the plugs 156 of that group are plugged into the path panel sockets 158. With switch 130 of the related synchro still open, the set can be carefully lowered to the stage, with manual rate control. Then switch base 138 can be adjusted. Similarly, switch base 136 can be adjusted to locate the set at the proper height in 'the fly-loft. Switch 130 can 'then be closed, putting the synchro of one winch motor ofa group in control of thegroup of motors. Other motors of this group may or may not have synchros; -but if they do, their switches 130 will be left open. Ordinarily about one winch motor in two or three will have a synchro, while the console may have only enough capacity (as to receiver synchros, push buttons, etc.) to -handle a predetermined munber of groups of winch motors. In such circumstances, any transmitter synchro of a winch motor can be plug-connected to any receiver synchro in the console, to function in controlling a group of motors.

Where two -alternators are used, two groups *of winch motors can be automatically operated simultaneously, in

spese;

13 pre's'et automatic operation of the other. Moreover, in the event of alternator failire, the remaining alternator can he operated a's` a stand-by unit, losing only the advantage of s multaneou's operation of difierently controlled groups of winch motors. i

Numerous variations in detail and van'ed application of the novel features of thedescrbed illustrated enrbodime'nt of the invention will occur to those skilled in the art,. and certain novel features may be employed without taking advantage of others; and consequently the inventio'' in its various aspects should be broadly construed, in accordanc'e with its full spirit and scope;

What I claim is: Y

1. Apparatus'for Operating. groups of lines supporting respective ,stage sets, ;wherein any selected group is to raise one stage set and; at the same time another selected group 'is to lower another stage set, including an individuaLwinch having a reversible electric drive motor for each line in each group of lines, two controllable sources of lect1 ic power selective means for connecting one group ot said electric motors to one ofsaidsources, for r l e p o t bv, d ,c n c e ns using the selected group of drive motors to operate all the corresponding winches towind in the lines and raise the stage set supported thereby, and further selective means for connecting another group of said motors to the other of said sources for controlled operation thereb S lld further connecting' means causing said other group of electric motors to operate the correspondng winchesto uiivind the related group of lines and lower the stage set connected thereto. V V

2, Apparatus for Operating groups of supporting lines connected to respective stage sets, wherein any selected group 'or lines is to raise one set atthe same time that another selected group is to lower another set, including winch means having reversible electric drive means for each group 'of lines, theelectric drive means of each group of lines including pl'ural synchronous motors, two contriollable sources of electi'ic power, 'and selective means for the electric drive means of any desired one 'of said groups of lines to one of said sources, said one source being related to the selected electric drive means to 'operate its winch means to 'raise its set, and for connecting the electrc drive means of any other desired group of lines to the other of said sources, said other source being related to said other electric drive means to operateits winch means to lower its set. I

3, Apparatus for Operating 'groupsof supporting lines connectedto respective stage sets, wherein any selected grupbt linesis to raise one set at the same time that anothergs'electedl group 'is to lower another set, including winch means having reversible electric drive means including plurl interconnected and 'electrically interl'ocked motors for each group of li nes, two controllable sources of e iect ric power, and selective means for connecting the el ctric 'drive means of any desired one of said groups of lines to one of said sources, 'said one source being related to the selected electric drive means to operate its winch means to raise its set, ,and for connecting the elagtn'c drive means of any other desired group of lines to'the other of; said sources, said other source being related to 'said other electric drive means to operate its winch means to lower its set, said selective connecting means including mul'tiple selectors, and inter-lock means between the selectors preventing any selected drive means from being connected simultaneously to both said sources.

41 Apparatus for Operating scenery 'supporting lines, wherein a selected line is to raise a set at the same time that another selected line is to lower another set, including for each line a winch having a reversible electric motor, two separately controllable sources of electric power, 'and selective means for connecting any desired one of said motors to one of said sources for raising its se: andfo'r connecting another desired one of said motrs' to 'the other of said sources to lower its set.

5.' Apparatus for Operating =`s'ce nery supporti`1g including a winch individual to each line having a 'ra- Vers'ible' electrio drive motor, 'two sources of electric power controll'a'ble separately for determining speed and directior` of-mot'or operation, and selective means for connectig any desired one of said motors to either oneof said sources, whereby any selected winch can be operated either to raise or lower tits stage set at the same' tinie that any 'other' :selected winch can be operated independently to raise or lower its stage set.

6. Apparatus for Operating scenery-supporting. lines, including' a. wi`nch `individual to each line having reversible electricdrive means, two sources of electric power co'ntrollable. s'eparately for determining speed and direction ,of operation of said electricdn've means, and selective means for connecting any desired one of said drive means. to either one, of said sources, whereby any selected winch` can be operated either ,to raise or lower its stage ;set at thesa'me time that any other selected: winch can be operated independently to raise or lower its stage st said selective means including multiple selectors having interlock means therebetween preventing anyselectedone of said drive. means from being connected simultaneouslyto both said sources.

:APParetu e ra ups of lnes pp n respective stage sets, wherein two sets are tobe operated concurrently but independently as to direction speed and duration, .including an individual winch having a reverible electr'ic drive motor tor eachline in each group of lines, controll'able sources of electric power, selective, means for connecting any desired group of electric motors to ether one of said sources for operation in either selected direction, and further selective means I for connecting any other desired :group of said motorsto the other o ft aid urcesvfor operation in either selected direction. u

8- a hea p a s se e eachav ng@ ef respondin g g je' of supprt'ng lines, an individual self-- looking winch fnyi' 'g a reversible elctric 'drive motor for `e'a`ch line, and means for seIectively connecting the motorsftogether; in gr ou for conjoint operation so t a u the g QIp offline s supporting each stageset can he "dperated by any accessible winches conjoin'tly operated b'y their coorjdinated meters'. i i

App ra i or %e n a o p of I P respective stage sets including for each line a'n individual winch having a reversible electric drive motor, and means fpr a ey connecting the mfotors together r r s; i f n mt pe o so hat nye ip' of lins, of' 'a stage set'can be 'operate' dby any desired' winch'es.

a o ,Amm u p rati grupsi o 'nes uppo n respective stage sets includingan individual self lockijg winch having a reversible electric drive motor for 'ech line', and means for s elech vely connecting the motors together in 'groups for conjoint operation so that any gropof'lines of a 'stage set can be operated by' any desired winches and 'selective 'means for energizing any desired group of said elect'ric motors to raiseo'r iwr a correspondingstgest;

'In atneee mr tgesets each haying aber; responding gtu' or 'su port ng lines, including I an indi vdl'al winch arki a rev'rs le' elctric motor for each'bfl said lines, switclioperable to connect 'coni' rently any selctedngroup of said motors source of'poiver p'ow'encontrol means coordinatd with' each groupof motors 'to control the' operationthreof at dfferent elevations of the stage set, and selective control means efective for' simultaneously connecting 'said power control means control relatio'n to said of power and for selectively Operating said switch means for connecting the corresponding group of said electric motors to the source of power. u

12. Apparatusfor Operating groups' of. lnes connected to respe'ctive, stage sets including an individual win h and a-reversible el'ec'tiic motor for 'each of said Iies `latio to 'said source of power and for selectively connecting the corresponding group. of said electric motors tothe sourceof power. x V u V V 13.: Appratu's' for Operating groups oftlinescornected to respective stagesets, wherein any'selected 'group is to operate one stage set and each other group is to operate another respective stage'set, including an individnal winch and a reversible electric motor for each of said lines, means' for connecting any desired group of said motors together, and a common motor Starter for connecting- 'any 'selected group of motors to' a source o'f power. r

14. Scenery handling apparatus' in` a theatre or the like having a stage, scenery units Suspended above 'the stage, lines secured to said scenery units at spaced points thereof, and individual winches distributed aloft, each line extending from a scenery unit to one of said winches, and electrical coordinating means for the winches controlling each scenery unit. v i

15. Scenery'handling apparatus in a theatre or the' like having a stage, scenery units Suspended above the stage, lines secured to said scenery units at spaced points thereof, laterally adjustably mounted sheaves located vertically above said spaced points, and individual electrically operated winches' distributed at fixed locations aloft, each line extending from' a scenery unit vertically to one of said sheaves and 'thence laterally to one of said winches. V V V "16. Scenery handling apparatus in a theatre-or the like having a stage, scenery units Suspended above the stage, lines secured to said scenery units at spaced points thereof, laterally adjustably positioned, sheaves located vertically above said spaced points, and individual electrically operated winches distributed aloft at fixed locations, each line extending from a scenery unit vertically to one of said sheaves and thence laterally to one of said winches, each of said winches including line guiding means at a fixed position in relation to the corresponding sheave and a cylindrical drum provided with both'rotational drive means and drive means for Shifting the drum in relation to the line guiding meanssaid drive means being related to each other to maintain the winding point of the drum opposite said line guiding means.

i 17, Scenery handl'ng apparatus in a theatre or the like having a stage, scenery units Suspended above the stage, lines secured to said scenery units at spaced points thereot, laterally adjustably positioned sheaves located vertically above said spaced points, and individual winches distributed aloft at fixed locations, each line extending from a scenery unit vertically to one of said sheaves 'and' thence laterally to one; of said-- winches each of said winches including line guiding means at fixed elevation and a vertical-axis drum provided with both rotational and vertical-travel; drive means related to maintain the winding point of the drum opposite said i line guiding' means, plural synchronous motors for opspaced points, anindividual winch having a fixed location aloft, a line extending from said one point vertically to said sheave *and thence laterallyto said winch, said winch including line guiding-means at` a fixed elevaton, and a drum provided with both rotational and aXial-travel drive means related to maintain the winding point of the drum opposite said line guiding means.

e 19. Scenery handling apparatus in 'a theatre or .the

like having a'stage, ,scenery units. Suspended abo've'the' stage`and lines secured to said scenery units atspac'ed' points thereof, s`aid apparatus including-a horizontally adjustably mounted sheave located vertically above one of said spaced points, an individual winch having a 'fixed location aloft,-.a line extending from said one point vertically to said sheave and thence laterally to said winch, said winch .including line guiding means at a fixed elevation, and a drum-provided with both'` rotational and axial-travel drive means related to maintain-the winding point of the drum opposite said line guiding means,

said'sheave and said winch each having a swivel bear ing with a vertical axis for automatically aligning the winch and the sheave along the line extending therebe stage, lines secured to said scenery units at spaced points thereof, horizontally adjustable' sheaves located vertically' above said spaced points, and individual winches distributed aloft, each line extending from ascenery unit vertically to one of said sheaves and thence laterally to a corresponding one of said winches, the winches that operate the lines from each scenery unit constituting a group, and plural electrically interlocked motors for each group of winches.

:21. Scenery .handling apparatus in a theatre' or the like' having a stage 'and scenery units Suspended by lines above the stage, said apparatus including a line-guiding sheave vertically above the place where each line is secured to a scenery unit, and a winch individual to each line mounted aloft, each winch having line guide means defining a winding point, said line guide means and said sheaves having vertical swivel bearings for automatic alignment thereof along a scenery-suspending line extending therebetween( i 22. Scenery handlng apparatus in a theatre orthe like having a stage and scenery units Suspended by lines above the stage, said apparatus including a line-guiding sheave vertically above the place where each line is secured to a scenery unit, and a winch individual to each line, the winches being mounted aloft, each winch having line guide means defining a winding point, said line guide means and said sheaves having vertical swivel bearings for automatic alignment of a sheave and the line guide means of the related winch along a scenerysuspending line extending therebetween, the lines from each scenery unitconstituting a group of lines and the corresponding winches' constituting' a group of winches,`

.23. Scenery handling apparatus in 'a theatre or the like having a stage, including a series of winches distributed aloft at fixed locations about the stage, each winch having a separatereyersible electric-motonsheaves mounted for horizontal adjustment to respective selected positions directly above the stage', and 'lines extending from saidwinches over corresponding sheaves to scenery units Suspended from those lines.

- 24. Scenery handling apparatus in: a theatre-or the like having a stage, including, a series of electricmotor driven winches distributed aloft and including a row of said winches across the rear' of the stage, scenery-supporting lines extending from said winches and secured to scenery at spaced points thereof, line-guiding sheaves I P Yy above said points, 'front-to-rear extending elongated members at a level above said winches, each elongated member having a close-spaced series of formations for securing sheaves thereto at any of numerous locations.

25. Scenery handling apparatus in a theatre or the like having a stage, including a series of electric-motor driven winches distributed aloft and including a row of said winches across the rear of the stage, scenery-supporting lines extending from said winches and Secured to scenery at spaced points thereof, line-guiding sheaves respectively above said points, front-to-rear extending elongated members at a level above said winches, each elongated member having a close-spaced series of formations for securing sheaves thereto at any of numerous locations, and a grid spaced suiciently below said winches'and said sheaves to enable Operating personnel to set up said winches, lines and sheaves as variously required.

26. In a theatre having a stage and flies above the stage for storing movable units of scenery, scenery handling apparatus including multiple lines connected to -a unit of scenery at respective spaced-apart points thereof, modular sheave locating and supporting means' above the stage, sheaves carried by said means, winches at spaced-apait locations about the files, said'lines extending over the respective sheaves to respective winches, in dividual synchronous electric motor drives for 'said winches, and common energizing and control means for coordinately Operating said motors.

27. In a theatre having a stage and fiies above the stage for storing movable units of scenery, scenery handlng equipment including a series of 'winches distributed about said flies, lines from said 'winches to said units of scenery, synchronous electric motors for said winches, and common control means for each group of said winches connected by lines to scenery elements of a given stage set, there being as many groups of winches as there are stage sets.

28. In a theatre having a stage and flies above the stage for keeping a series of stage sets available, scenery handling equipment including regularly. distributed winches along the rear and sides of the fiies, lines eX- tending from selected winches to supporting points of a stage set, said selected winches constituting a group of winches and there being as many groups of winches as there are independently operable stage sets, individual synchronous electric motors for said winches and common control means for the motors of each group of winches, said control means including a controlled-frequency alternating current source. v

29. In a theatre or the like, scenery handling equipment including gridiron, multiple flying sets, including sets of non-fiat form and having supporting lines extending vertically from out-of-line points along the top edges thereof, adjustable sheave supports spaced above the gridiron, and sheaves distributed thereon in accordance with the distribution of lines from the stage sets, a multiplicity of winches fixed at positions distributed about said gridiron, each line extending to a respective winch, and a coordinated drive means for each group of winches to wmch lines extend from correlated portions of a stage set, there being at least as many winches as lines and as many groups of winches as independently operable stage sets.

30. Scenery handling apparatus in a theatre or the like having a stage, scenery units Suspended above the stage, a group of lines secured to each scenery unit at spaced points thereof, a plurality of winches distributed aloft, each line extending to a separate one of said winches, an individual electric motor for each of said winches, the winches and motors related to each group of lines constituting a group of winches and a group of motors, respectively, switch means to connect any desired group of motors to a source of power for conjoint operation to shift the related scenery unit, a transmitter synchro coupled to one winch of each group;

plural receiver synchros at a remote control station, each receiver synchro being connected to -a corresponding transmitter synchro, and means controlling the operation ofsaid electric motors, said control means being operable by said receiver synchro to limit operation of said connected group of motors when the corresponding scenery unit has been caried by its group of winchesto a preset' limit of travel of that scenery unit. v

31. Scenery handling apparatus in a theater or the like' having a stage, including a series of winches distributed aloft, each winch having a separate electric motor and a supporting line extending from each winch over guide means to a respective point of suspension of a scenery unit, a power line extendng past said electric motors, plural relays operable to connect respective motors to said power line, said relays having control lines to a remote control point and being connected to each other in groups at a patch panel at said remote con trol point, the relays of each group being related to the lines of each group supporting a scenery unit, and se# lective means for Operating any one group of said relays thereby to connect the related motors of that group to the power line for Operating the scenery-suspendng lines of the related motor-operated winches.

32. Scenery handling' apparatus in a theater or the like having a stage, including a series of winches distributed -alof t, each winch having a separate electric motor and a supporting line extending from each winch over guide means to a respective. point of suspension of a scenery unit, a power line extendng past said electric motors, plural relays assembled to said electric motors and operable to connect the respective motorsto said power line, said relays having control lines to a remote control point and being connected to each other in groups at a patch panel at said remote control point, the relays of each group being related to the lines of each group supporting a scenery unit, and selective means for operating any one group of said relays thereby to connect the related motors of that group to the power'line for Operating the scenery-suspending lines of the related mo tor-operated winches, one of said electric motors of. each group having a transn'itter synchro coupled thereto, a receiver synchro at the remote control station connected to the respective transmitter synchro of each group of motors, there being as many patch panels as there are receiver synchros, a controllable source of power connected to said power line, and control. means operated by said receiver synchros for controlling said power source automatically in accordance with the position of the corresponding scenery unit relative to its upper and lower limits, said selective means for Operating said groups of relays additionally including means for connecting the control means of each receiver synchro in control relation to said source of power.

33. Apparatus for Operating groups of lines connected to respective stage sets, including an individual winch and a reversble electric motor for each line, means effecting coordinate operation of each group of motors connected by supporting lines to individual stage sets, one winch in each coordinated group having a transmitter synchro mechanically connected thereto, plural receiver synchros at a remote control station connected respectively to the transmitter synchros, said remote control station being at a vantage point in view of the stage, and control means for said motors including rate controI means individual to each receiver synchro and operable thereby to reduce motor speed when the stage set related thereto approaches either its lowermost or uppermost limit, and manually operable motor speed control means effective throughout the range when said rate control switches are not in effect.

34, Apparatus for Operating groups of lines connected lock'ng winch having a reversible electric motor for each scenery-supporting line, 'two controllable sources of powr pairs of relays at said motors for connecting each motor to either oli-said sources, 'plural means for interconnecting said relays in groups for enabling connection of--s'aid motors in corre sponding groups to either otsaid c'ontrollable sources, the motors thus* grouped' corre s'ponding to the lines connectedto said stagesets, respc tively, a transmitter synchro coupled *to one; winch. of each' group for coordinate operation therewithQ a receiver synch 'o at a remote 'control station connected to 'eachrespective' transmitter synchro, control means op'- erated by eachreceiver synchro in relation to'the winches related 'thereto and including up' rate 'and switches an-down fate and limitswitches, and group selectiing"'me'an 's,` s aid last-named means including a 'pair 'of s'lctdrsfor each group of motors and, correspondingly, for each stage set, one selector of each pair having contacts for energizing those interconnectedrelays of each group of motors that connect such motors to one of said sources ,of power simultaneously and said one selector also having contacts for connecting the related rate and limit switches of that group of motors in control relation to said one source of power and the other selector ot each pair of selectors havingiconta'cts for energizing those inte'rconnected relays of each group of motors that connect` such motors to the other of said sources of power simultaneously, said other selector of each pair of select o 's also having contacts for connecting the re latedrate and limit switches of that groupof motors in control relation to 'said other sourceof power, one of i s'aid sources having respective direction control connec tions tothe grouped' motors connected thereto to operate said groups of lines for controllably raisng the related stage set and the other of the sources of power` having direction control connections to the motors'c'on nected thereto to lower the related stage, set under independent control, whereby any desired group of motors can be selectively energzed to rase' one stage set and another selected group of motors can be operated at the same time to lower another selected stage set, other stage sets not selected being operable subsequently for rasing or lowering under control of it s related pair-'of selectorsi i v i `35. Scenery handling apparatus in ,a theatre or the like in accordance with claim 23, including a 'grid spaced below sad sheaves by a distance toenable Operating personnel to adjust said sheaves and arrange said lines 5 thereoverg '36. In a theatre having a stage and fies above the stage for keeping a series of stage sets readily available, and set-handlng apparatus including a series of winches distributed aloft at fixed locations, said winches having unform-diame'terdrums and means providing a constant winding point, sheaves above the stage, adjustable locatin'g and supporting means for the sheaves, lines extending from said winches over said sheaves and vertically downward to respective suspension points of the sets, said sheaves' having vertical-artisi swivel bearings for alignng each sheave with a corresponding winding point of one of said winches, a synchronous alternating-cu'rent motorfor each winch, a controlled-frequency alternating current power source and a power line extending from said power source adjacent to the motors of said winches', grouping means operable to connect the motors of eachstage set to .the power 'line concurrently, and f'equency control means for said power source to provide controlled-speed coordinated operation of the lines supporting each stage set when the synchronous motors of said winches are connected to said power line.

37. Scenery handlng apparatus in a theatre or the like having stage sets Suspended above the stage and having supporting lines Secured thereto at space'd points, sheaves adjustably located vertically above said spaced points, a ;series of winches distributed aloft at fixed locations, each of said winches having a synchronous electrie -motor, the lines of each stage set extending over respec- 'which operate the winches-and the supporting lines of each stage set 'constituting a group of motors, a pair of power lines extending past said electric motors, selective means operable to connect a selected group of said motors to one of said power lines and to connect another selected group of said motors to another of said lines, a pair of variable-frequency alternating-current power Supplies for said power lines, separate means for adjusting the frequencies of said power Supplies, and respective control means coupled to the motors of each selected group and operable coordinately therewith for separately adjusting the respective' frequencies of the alternating-current power Supplies in accordance With the elevation, relative to the stage, of each stage set being operated.

References Cited nthe file of this patent UNITED ASTATES VPATENTS Weidhass et al. Mar. 7, 1933 Lassen et al May 21, 1935 Fischer Jan. 20, 1953 

